Fluid delivery and aspiration catheters are well known in the art. Catheter devices using the Coanda effect for various purposes are known as well. See for example U.S. Pat. No. 5,284,473 to Calabria and U.S. Pat. No. 5,344,395 to Whalen and Willard.
Specialized thrombectomy catheters, which rely on injected fluid to interact with occlusive material, are also know. U.S. Pat. No. 5,320,599 to Griep et al. appears to describe a device sold in the trade as the “Hydrolyzer.” This device uses a “free” jet pointed in a retrograde direction to entrain ambient material in a blood vessel and to emulsify and propel this material out of the body.
Specialized distal protection devices are also known. See for example U.S. Pat. No. 6,135,991 to Ketan Muni, which describes the use of an occlusion device such as a balloon, to trap embolic particles released by a therapy such as angioplasty or the like. In operation the occlusion device is deployed proximal of a therapy device. After a therapy has been performed an aspiration catheter may be exchanged for the therapy catheter and debris removed from the location of the therapy by suction. It has also been suggested to use a rheolytic or Possis device with a balloon.
One problem with these prior art approaches is the inability to “see” the occlusion or treatment zone with contrast agent. The occlusion device prevents flow through the zone which forces the physician to work “blind” in the vessel.